Baton Rouge-based Business First Bank has reached a deal to acquire north Louisiana's Richland State Bank in a $51 million deal that will make Business First the fourth-largest bank headquartered in Louisiana.

The deal includes $10.6 million in cash and around 1.6 million Business First shares, which based on the most recent share price of Business First values the deal at $50.8 million. The deal is subject to regulatory and shareholder approvals and is expected to close in the fourth quarter.

Business First on Monday also announced it began on offering of 900,000 shares of common stock, aimed in part at funding the cash portion of the acquisition. The bank will grant underwriters a 30-day option to purchase up to 135,000 additional shares. The remaining funds raised through the public offering will be used to strengthen the firm’s capital position.

If approved, the acquisition of Richland State will put Business First at about $2 billion in assets.

The move follows Business First’s acquisition of Minden Bancorp, a $76 million deal that closed in January. In April, Business First went public with a direct listing on the Nasdaq exchange. The bank now has 19 offices, including 18 banking centers, in markets across Louisiana and Texas.

"Our team remains focused on our goal of becoming the region's most influential business-focused community bank," said Jude Melville, Business First president and CEO. "This merger, in combination with our recent MBL Bank partnership in Minden, Louisiana, expands our presence along the I-20 corridor and provides diversification and balance to our business mix."

Richland State Bank is headquartered in Rayville and has seven branch locations throughout north Louisiana. It was founded in 1902. As of March 31, Richland had $305 million in assets and $788,000 in net quarterly income.

Stephens Inc. is serving as the lead book-running manager for the public offering of stock. Raymond James and Associates Inc. is serving as the lead manager, and Hovde Group LLC is serving as co-manager.

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